Precautions

It is very important that your doctor check your progress at regular visits. Your doctor may want to do certain blood and urine tests to see if the medicine is causing unwanted effects.

This medicine may cause serious problems with your liver. Call your doctor right away if you start having dark urine, pain in the upper stomach, or yellowing of the eyes or skin while you are using this medicine.

This medicine may increase your risk of having a lung disease called eosinophilic pneumonia. Tell your doctor right away if you have coughing or trouble breathing after receiving this medicine.

This medicine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a rash, itching, hoarseness, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you are using this medicine.

You will need to stop using opioids (narcotics) for at least 7 to 10 days before you can start receiving naltrexone injection. Your doctor may need to do the naloxone challenge test or a urine test for opioids to make sure you are opioid-free.

This medicine blocks the "high" feeling you get from narcotic (opioid) drugs, including heroin. Since naltrexone injection may make you more sensitive to lower doses of opioids than you have previously used, you should not use heroin or any other narcotic drugs to overcome what the medicine is doing. You could overdose and develop serious problems.

This medicine may increase thoughts of suicide. Tell your doctor right away if you start to feel more depressed. Also tell your doctor right away if you have thoughts about hurting yourself. Report any unusual thoughts or behaviors that trouble you, especially if they are new or get worse quickly. Make sure your caregiver knows if you feel tired all the time, sleep a lot more or a lot less than usual, feel hopeless or helpless, or if you have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. Also tell your doctor if you have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared.

Remember that use of naltrexone is only part of your treatment. Be sure that you follow all of your doctor's orders, including seeing your therapist and/or attending support group meetings on a regular basis.

Do not try to overcome the effects of naltrexone injection by taking narcotics. To do so may cause coma or death. You may be more sensitive to the effects of narcotics than you were before beginning naltrexone treatment.

Naltrexone injection also blocks the useful effects of narcotics. Always use a non-narcotic medicine to treat pain, diarrhea, or a cough. If you have any questions about the proper medicine to use, check with your doctor.

Naltrexone injection will not prevent you from becoming impaired when you drink alcohol. Do not take naltrexone in order to drive or perform other activities while under the influence of alcohol.

After naltrexone is injected into your body, it is impossible to remove it.

It is recommended that you carry an identification card stating that you are receiving naltrexone injection. You may also need to carry a letter to let others know you are receiving this medicine in case you have a medical emergency.

You may experience a serious reaction at the site of the naltrexone injection that includes pain, swelling, tenderness, bruising, itching, and redness. Contact your doctor right away if this skin reaction does not improve or becomes worse within two weeks after receiving the injection. Your doctor should also refer you immediately to a surgeon.

You may experience nausea after the first injection of this medicine that should be mild and subside a few days afterwards. You will be less likely to have nausea with your next injections.

This medicine may cause some people to become dizzy, drowsy, or less alert than they are normally. If any of these side effects occur, do not drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert while you are receiving naltrexone injection.

Before you have any medical tests, tell the medical doctor in charge that you are receiving this medicine. The results of some tests may be affected by this medicine.